| About this Abstract |
| Meeting |
MS&T21: Materials Science & Technology
|
| Symposium
|
Grain Boundaries, Interfaces, and Surfaces in Ceramics: Fundamental Structure—Property—Performance Relationships
|
| Presentation Title |
Influence of Planar Defects on the Electrochemical Cycling and Diffusion of Li in LixMn2O4 |
| Author(s) |
Torben Erichsen, Cynthia A. Volkert |
| On-Site Speaker (Planned) |
Cynthia A. Volkert |
| Abstract Scope |
Planar defects are present in the pristine and cycled transition metal oxide nanoparticles used in battery cathodes, and are expected to impact charging kinetics and capacity of Li-ion batteries. In this study on LixMn2O4, we use in-situ transmission electron microscopy (TEM) and atom probe tomography (APT) to investigate the effect of planar defects on redistribution of Li during charging and discharging. Both APT and in-situ TEM show that (111) stacking faults can either accelerate or block Li diffusion, while APT of partially delithiated LixMn2O4 tips reveal a strong dependence of Li mobility on Li concentration. We explain these results with a simple model for vacancy mediated diffusion of Li on tetrahedral sites. The planar defects generated during charging into the x>1 region impose additional obstacles to Li diffusion and may account for the capacity fade observed in Li-ion batteries. |